— INTRODUCTION —
Audacity version specific information is for 1.3.14 at this writing.
The elves on the Audacity Help Forum get the same questions about sound recording on Windows computers over and over. By "sound," I mean music, singing, playing a musical instrument or other sound art, drumming, playing a tape or vinyl record. Anything other than a single person speaking which is a special case.
Windows machines, particularly the later models are designed for conferencing, corporate communications, meetings, roundtables and content sharing in the field or locations away from the business office. They're not so good for recording a guitar solo. They're not tape recorders.
— CONNECTIONS —
Large desktop or office Windows machines typically come with a sound card and connections such as three colored jacks.
From top to bottom:
- Green is generally stereo Line-Out. High level stereo sound comes out of this jack and you can connect it to small stereo speakers, earbuds, stereo headphones, or a lead to the "AUX IN" on your large stereo sound system, or larger amplified computer speakers.
- Blue is the next and it's usually stereo Line-In. This is the connection that will accept sound from a high-level stereo sound device such as a stereo mixer, cassette or reel-to-reel player, the analog connections of a USB turntable, the headphone output of an MP3 Player or even a CD or DVD player — portable or not. Microphone preamps and guitar pickups fall into this group even though they're not stereo.
Both Line-In and Line-Out can be connected to other sound equipment (and to each other) with a stereo jumper cable or a stereo adapter cable or other adapters as needed.
- Pink is last and is usually Mic-In. It's mono, not stereo, it carries special internal wiring and is designed to be sensitive to the very low level, delicate signals coming from a microphone such as an analog headset.
If you plug something powerful and stereo intended for the blue jack into the pink jack, you can be missing the right channel of the stereo music and the left channel has a good chance of being too loud, horribly distorted, crackly, popping or crunchy. There is no recovery. Because of the way microphone connections work, you usually can't simply adjust your way out of trouble and there are no Audacity tools to repair the damage. You may never get the right channel of music recorded at all.
It's common for Windows laptops to be missing the blue jack.
Some laptops have a blue jack and some laptops have the ability to switch one jack between stereo and mono, but those are not common. Consult your computer instructions. Another recent arrival is the "Mic Line-In." That's usually just another name for the pink Mic-In jack. Read your instructions.
You can artificially create a "blue jack" or high level stereo input with an external USB sound device such as the Behringer UCA-202.
There are three Vista/Win7 conferencing services which make your voice sound terrific when you're speaking between time zones to the business office for one example, but which can destroy music or other sound recording.
- Echo Cancellation. Windows "knows" about conference voices arriving from the far locations. It mutes your microphone during received voices and echoes from your walls. It also has to "know" when you're speaking to allow your voice to go through undamaged. It's a juggling act. Sometimes it takes a second or two for Windows to figure out who you are and how large your room is.
This can put holes in the sound when you're trying to overdub or multi-track.
- Auto Level Setting. The computer tries to determine your normal speaking volume and adjust it so it fits gracefully into the conference along with all the other voices in the meeting. There is nothing like having a multi-part corporate conference call where one voice is explosively louder than all the others. Windows adjusts volume automatically.
This can give you a music recording with no expression. No matter how loud or soft you sing or play, the show stays the same volume.
- Environment Cancellation. Windows will "listen" to your voice and try to determine which are the sounds likely to interfere with you such as air conditioning, traffic, music, cooling fans or other room noises and it tries to fade, adjust, and filter them out of the conference.
The symptoms of this happening are a perfect music recording for a certain number of seconds and then your music fades and gets honky, gargling, bubbling or starts sounding like playing into an empty barrel.
We wrote about how to adjust Windows Control Panels to turn these services off.
This is also known as Recording Computer Playback.
In general, you record internet sound by recording from a special Windows device such as Stereo-Mix, Mix-Out, Wave-Out or What-U-Hear. That's the last thing you want when you're recording your guitar because that setting may give you echoes, repeats, double notes or other feedback effects and distortions.
Record directly from stereo Line-In, Mic-In (if you have a headset microphone or computer microphone), Built-In Microphone (if you have one) or a USB adapter or USB microphone if you decided to buy the hardware. You can select these in Audacity by changing settings in the Device Toolbar .
Sound-On-Sound, Multitrack and Overdubbing is covered in another paper.
It's pretty common to think you're going to create a terrific quality show from your music by recording it through your sound card.
Probably not. Built-in sound cards and sound services are throw-away computer features only put there because everybody is expecting them. Few people try to record any sound, ever, and only use the computer to write spreadsheets, update their Facebook page and watch YouTube. A high quality sound card for them is a complete waste of money.
Sound cards have several strikes against them. They're cheap quality and have to live inside the hot, insanely noisy and inhospitable computer case. If you have a computer where you can change the sound card, the instructions with a new one generally warn you to install it far away from everything else as you can. I have one PC sound card that is noisy on one channel and that's just the way it is. There are no guarantees with these things and many computer advertisements don't even mention them.
I noted the Behringer UCA-202 above and that's a good way to get a reasonable quality external sound card away from the computer's heat and electrical noise. Behringer makes a number of different sound cards -- some have phono preamps built-in like the UFO202 for those trying to convert that pile of vinyl records in the garage to MP3 or music CD.
— USB Oddities —
Plug in USB devices before you start Audacity. "I plugged in my new USB microphone and it doesn't work!" Once Audacity is running, it stops checking for new arrivals. Transport > Rescan Audio Devices to force a check on arrivals or departures, but restarting Audacity is bulletproof.
When you plug in a USB sound card, USB microphone, or other USB sound device into a Windows machine, Windows is likely to assume that the new kid on the block is the only kid on the block. That is, Windows assumes that it needs to accept audio from the new device, but it also tries to play it back there when you finish the recording. This is entirely desirable if you have a USB headset with both headphones and microphone suitable for a conference call (see Windows Conferencing, above). It doesn't work nearly so well if you have a simple USB microphone or USB connections for your turntable or tape machine.
"I recorded my Theremin and Sackbut duet and now it won't play back. I can see the blue waves and the green sound meters are jumping, but I can't hear a thing."
— Or better —
"I recorded my dog barking and now all the sound on my computer is dead!"
Not dead, just misdirected. The easiest remedy for all your applications, not just Audacity is unplug your USB device. Windows should revert to the way it was before.
If you leave your USB device connected, you can set the Audacity Device Toolbar so your speakers or headphones work again, but other applications (Firefox, Windows Media) may require changes to your Windows Control Panels. Sorry, but this is how Windows handles USB and happens whether or not you have Audacity.